Pneumatic tire and rim assembly



July 20, 1943. J. E. HALE 2,324,994

PNEUMATIC TIRE AND RIM ASSEMBLY Filed June 7. 1941 4 JAMES E.HA|.E

Patented July 20, 1943 PNEUMATIC TIRE AND RIM ASSEMBLY James 'E. Hale,Akron, Ohio, assignor to The Firestone Tire & Rubber Company, Akron,Ohio, a

corporation of Ohio Application June 7, 1941, Serial No. 397,103

' 4 Claims. (c1.152 4o1 This invention relates to pneumatic tire and rimassemblies, especially to assemblies adapted to retain a pneumatic tirethereon and in forcetransmitting contact therewith, even though operatedwhen deflated.

When pneumatic tires are mounted on a conventionl rim which issubstantially cylindrical and has a removable side flange mounted on oneedge, it is obvious that the inside diameter of the tire bead must beslightly larger than the bead seat diameter of the rim in order that thetires can be readily and conveniently applied to, and removed from, therim by the simple action of telescoping the tire beads over the rim.

In driving a vehicle, or in braking it, the forces producing the change'of motion of the vehicle must be transmitted through the tire withoutthe tire slipping or creeping on the rim. It is found that with properlyinflated tires this is accomplished through the fact that there issuflicient lateral pressure on the vertical faces of the beads that theyare forced into tight frictional contact with the vertical faces of theside flanges sufficiently to accomplish this.

It is possible to compute the forces developed by this lateral pressureon the side flangeand prove that if the pressure is suflicient there isno need of any auxiliary means of providing the driving or tractiveforce, or the braking resistance for the vehicle so long as therequisite air pressure exists in the pneumatic tires. However. if, forany reason, the air pressure in the tire becomes so low in relation tothe conventional air pressure, orthe air pressure in the tire iscompletely exhausted, then there will be an absence of sufficientpressure forcing the beads against the flange to provide this action.Accordingly, in that event, it is necessary to provide for lateralpressure against the flanges.

Attempts have been made to provide pneumatic tire and rim assemblieswhich'can be operated, even though the pneumatic tire carried thereon isdeflated, without rotating the tire on the rim, or pulling the tire offthe wheel. These constructions generally involve use of some type ofannular pressure member carried on a circumferentially divided wheel, orrim, and adapted to exert pressure upon the beads of a mounted tire andforce same out against the rim flanges. However, substantially all ofthese constructions involve the use of a continuous compressible memberreceived between the tire beads and are costly, while also usinga massof rubber, or similar substance which may be difficult to obtain.

The general object of this invention is to Pro: vide mechanical meansfor insuring that a. definite pressure forces the beads of a pneumatictire against the side flanges of the rim on which it is positioned, eventhough there is no pneumatic pressure in the tire. Such mechanical meansmay be termed a bead lock."

Another object of .the present invention is to provide a bead lock typeof pneumatic tire as-' sembly that effectively secures the tire beads infixed relation to a rim and that overcomes the foregoing and otherdisadvantages of known constructions.

Another object of the invention is to provide a bead lock tire assemblyadapted to use standard type fiat base rims having either a continuousor a discontinuous removable side flange thereon ordinarily received ina gutter formed at one extremity of a rim base.

Still another object of the invention is to position a pneumatic tire ona cylindrical rim so that the tire beads are held in driving contactwith the rim flanges regardless of the volume of air within the tire.

A further object of the invention is to provide a bead lock constructionwhich can be placed in inoperative position during assembly of the wheeland which thereafter can be readily brought into operative position.

The foregoing and other objects will be mani fest as the specificationproceeds.

In the accompanying drawing:

'Figure I is an elevation, partly in section, of a wheel assemblyembodying the invention;

Figure II is a transverse section taken on line IIII of Figure I, with atire mounted thereon;

and

Figures III and IV are transverse sections of the wedge 'means, taken onlines III-III and IVIV of Figure I. 7

Referring specifically to the accompanying drawing, a standard type flatbase rim H is provided which has an integral rim flange l2 at oneextremity thereof and aside ring receiving gutter 13 formed at the otherextremity thereof. A rim side ring M of standard construction isreceived in the rim gutter l3. A standard pneumatic tire I5 isreceived'on the rim 1 I, which tire may have a tube I6 received therein,said tube being of the self-sealing type.

The bead lock means of the invention include an annular metal band I!made from springy material, which. band is designed and arranged so thatit fits snugly on the outer periphery of the rim I I and can be readilytelescoped thereon when the rim side ring I4 is removed. A plurality ofcircumferentially spaced metallic locking blocks I8 are secured to theband I! and are adapted to be received between the beads of the tire IS.The blocks are of such size that they force the tire beads outwardlyagainst the rim flanges when they are adjacent the band I! and so thatthey are entirely free from the tire beads when moved to their radiallyouter positions, as hereinafter described. Any suitable number oflocking blocks may be used, as long as they are balancedcircumferentially of the wheel assembly and are present in suificientnumbers to insure locking:

the beads of the tire I5 against the rim flanges, as hereinafterdescribed. The metal blocks [8 are wedge-shaped in section, as shown inFigure II, with the radially outer surface of the block being largerthan the radially inner sifl'lace, which is slightly arcuate in alongitudinal direc tion and which, in operative position, may abutofibeau l1. bloclis If are secured to the bahd [-1 by' Suitable lostmotion connectors, it this case, comprising" headed pins I8 which arereceived iriapertures 22 extending through the lilocfis l8. Shoulders z:are formed in the a ertures 22 adjacent the radially inner surface ofthe blocks, that a reduced diameter section is formed adjacent the innersurfaces of the brooks. The heads of the pins [9 are adapted to seatupon the shoulders 23 and limit radially outward movement of the blockswith relation to the band H. Note that the ends of the blocks I8 arecored out at 24 in order to cut down the weight of the blocks, and theouter surfaces of the ends of the blocks may .be beveled 05 or roundedoff longitudinally, if desired. A coveringmaterial 25 may be. placedover the outer surface of the blocks. This covering may be made fromfabric, or rubber, or other suitable material, and it serves to" protectthe portion of the tube 16 contacting the block.

The positions of the blocks IS with relation to the band H arecontrolled by screws 28 that extend through holes 21 formed in the rimbase If and through holes 28 formed in the band 11. These screws 26engage with tapped holes 29 formed-in the centers of the inner surfacesof the blocks l8. Usually either the holes 21, or the holes 28 aretapped in order that the screw 26 is in positive engagement either withthe rim base II or the band N. Then by engaging the screw with thetapped aperture 29, the blocks 08 can be positively positioned radiallywith relation to the band H and, in turn, with relation to the beads ofthe tire l5. This should be done before the tire is assembled on therim. However, it may be desirable to mount the ring H and the wedgeblocks within a tire before mounting same on a, rim. Then neither hole21 or 28 should be tapped, and'the screws 26 would be engaged with theblocks after the tire is mounted on the rim. In all events, the blocksare to be placed in their inoperative, or non-wedging positions when therim side ring is positioned. a Radially extending lugs 3| may be formedon the tapered side surfaces of the blocks l8 to set up friction betweenand obtain a better grip on the tire beads, when the blocks are incontact therewith.

in assembling the wheel construction of the invention, the screws 26 arefirst engaged with the blocks [8 onlya short distance so that the blocksl8 can be positioned in radially spaced relationship with the rim basell. When the wheel is completely assembled, the screws 26 should betightened to draw the blocks [8 down into engagement with the beads ofthe tire I 5 and force them outwardly tightly against the rim flanges.Preferably, the blocks are drawn in against the tire beads substantiallyuniformly. In disassembling the wheel, the air within the tube l8 shouldbe valved therefrom, after which the blocks l8 should be movedradiallyoutwardly from the band [1 by looseningthe screws 26. Then the rim sidering 44 can be removed from the ring base II, as in standard practice,and the tire removed from the rim.

fiiactual tests of the bead lock wheel construction shown herein, highlydesirable results have been obtained, and wheel constructions have beenoperated for many miles with no air pressure in the pneumatic tire,while the blocks have heid the tire upon the wheel assembly and enabledoperation thereof, The only requirement in adapting standard riznassemblies to applicants apparatus, is to; provide holes in the rim basethrough which the screws 28 can be eflg'i ged with the l8. The presentwheei constriietioh is easily manufactured and assembled and the objectsof the invention are achieved therefiy'.

What is claimed is':-'

1. In a wheel construction for a pnei'uuatic tire, a; hat rim basehaving an integral flange at edge thereof, a removable side ringforminga second flange for the rim base positioned at the other edge orsaid run base, a continuous metal band fitting onto the periphery ofsaidrim base, a plurality of metal blocks fitting on said band, aplurality of headed pins securing said band to said blocks, said pinsbeing received in apertures formed through said blocks, said apertureshaving shoulders'form'ed therehi adgacent the inner surfaces of saidblocks with which said headed pins engage but which allow limited radialmovement of said blocks with relation to said band before engagingtherewith, each of said blocks. having a tapped recess extendingthereintd from the inner side thereof,

. each of said blocks being wedge shaped in section and Being narrowerin the side thereof ad.- jacont said bandthan in the side thereofremoved from said bond, and screws securing said band to said rim andengaging with the tapped recesses in said blocks whereby said blocks canbe positively moved radially outwardly from said band even after a tireis assembled on said rim, said blocks being of such size as to lock thebeads of a pneumatic tire against said rim flanges when drawndown'adjacent the periph cry of said band but to be free from the beadswhen moved to their radially outer positions.

2. In a wheel construction including a rim adapted to mount a pneumatictire, and a re movable flange member for the rim, a continuous metalband adapted to fit snugly upon said rim, a plurality of metallicblock's wedge shaped in section and wider at their tops than at theirbases, means securing said blocks in circumler entially spaced relationto said metal band with the bases of said blocks being adjacent theouter surface of said metal band, said means enabling lost motionbetween said blocks and said band in a radial direction,- and meanssecuring said band to a rim base and controlling the relative radialpositions of saidblockswith relation to said metal band, said meanscomprising bolts extending through the rim for threaded engagement withthe blocks, said blocks being of such size as to press the beads of apneumatic tire on said rim tightly against the flanges of the rim andlock the tire thereon, when drawn into clamped engagement with the rim.

3. In a rim and tire assembly, the comb-inaof circumferentially disposedspreader blocks,

frustro-conical in cross section and attached apex inwardly to the band,said blocks being provided with spaced apertures and said band beingprovided with outwardly extending pins having head portions disposed insaid apertures and means preventing withdrawal of the pin head portionsfrom the apertures to enable movement of the blocks in a directionradial of said band while securing against block movementcircumferentially thereof, and clamp means extending through the rim andthreadedly engaging the blocks whereby the blocks may be drawn towardthe rim under pressure to maintain the tire beads locked in pressureengagement between the rim flanges and the blocks.

4. In combination with a pneumatic tire and rim assembly of the classdescribed, a bead lock: ing device comprising an inextensible endlesshaving a plurality of rigid wedge-shaped tire beadclamping units securedthereto by lost motion connectors, said units being arranged incircumferentially spaced relation about said band and having centrallylocated threaded apertures adapted to engage in threaded relation withbolts projected radially outwardly throughholes formed in the base ofsaid rim, whereby said clamping units may be drawn radially inwardlyfirmly against said tire beads and JAMES E. HALE.

